tbuckley/cabot-search huggingface dataset:
Abstract P1038: Exosomal RNAs And Proteins From Non-invasively Derived Human Induced Mesenchymal Stem Cells Protect Cardiomyocytes From Death
Authors: Narasimman Gurusamy, Vinoth Sigamani, Selene Perales, SHEEJA RAJASINGH, Johnson Rajasingh
Journal: Circulation Research (2022)

Background: Current stem cells therapy for ischemic cardiomyopathy is effective only about 2-4% in improving cardiac function. In search of novel therapy, we have developed a safe mRNA-based reprogramming of non-invasively derived human urinary epithelial cells into induced pluripotent stem cells (iPSC), and subsequently differentiated them into mesenchymal stem cells (iMSC). We examined therapeutic potential of iMSC in comparison with adult umbilical cord mesenchymal stem cells (MSC). Hypothesis: Autologous iMSC and their exosomes possess an enhanced cardioprotective characteristics compared to MSC. Methods and Results: The generated iMSC and their exosomes (ExoQuick reagent) offered an enhanced protection of human iPSC-derived cardiomyocytes (iCMC) from injuries of (i) angiotensin-II (Ang, 10 μM for 24 h) and (ii) 6 hrs of 1% hypoxia and 24 hrs of reoxygenation, in comparison with their MSC controls. The cardiomyocyte protection was studied through measurement of mitochondrial membrane potential (JC1 dye), intracellular reactive oxygen species (CM-H2DCFDA), in situ cell death by apoptosis, and qRT-PCR expression of survival and proinflammatory genes (BCL2, BAD, TNFA and IL6). Treatment with iMSC-derived exosomes alone enhanced the expression of NRF2, a major regulator of cytoprotective genes in protecting Ang-challenged iCMC. The specific role of iMSC exosomal RNAs and proteins in mediating cardioprotection against Ang-induced injury was identified through in situ cell death assay using the exosomes treated with either RNase A (0.5 μg/μl for 20 min at 37 0 C) or proteinase K (0.05 μg/μl for 10 min at 37 0 C) (Fig.1) . Exosomal noncoding RNA analysis by qRT-PCR revealed the presence of inflammation-associated small nucleolar RNAs such as SNORD32A, SNORD33, SNORD34 and SNORD35A. The transfer of exosomal RNAs into the host cardiac cells was augmented in presence of Ang, identified using 0.5 mM ethynyl uridine-labelled exosomes and detected using Click-iT RNA imaging reagents. All experiments were carried out in triplicates. In vivo studies are in progress. Conclusion: In comparison with adult MSC, non-invasively derived autologous iMSC and their exosomes elicit enhanced cardioprotection and may provide an alternative source of cells or cell-free therapy for treating ischemic cardiomyopathy.
Abstract P2115: Differential Cardiac Remodeling Profile Of Immunosuppression Drugs
Authors: Karim Sallam, Dilip Thomas, Sadhana Gaddam, Nicole Lopez, Aimee Beck, Ryan Dexheimer, Leila Y Beach, Albert J Rogers, Hao Zhang, Ian Y Chen, Mo Ameen, William Hiesinger, Jeffrey Teuteberg, June W Rhee, Kevin Wang, Nazish Sayed, Joseph C Wu
Journal: Circulation Research (2022)

Introduction: Heart transplantation provides lifesaving therapy for patients with end-stage heart failure. The longevity of the therapy is limited by Cardiac Graft Dysfunction (CGD), which is an acquired cardiomyopathy affecting transplanted hearts associated with diastolic and/or systolic dysfunction. Some clinical risk factors for CGD have been identified, but none of them are easily modifiable. An unexplored potential contributor to CGD is the choice of immunosuppression agent used despite multiple clinical reports suggesting reduced adverse cardiac remodeling with mammalian target of rapamycin (mTOR) inhibitors compared to calcineurin inhibitors (CNI). This study examines mechanisms of differential cardiac remodeling effects of CNI versus mTOR inhibitors in a human cellular cardiac model. Methods/Results: We utilized 3D cardiac spheres composed of induced pluripotent stem cell-derived cardiomyocytes, cardiac fibroblasts, and endothelial cells (cardiac organoids). Cardiac organoids were treated with 5 days of vehicle, tacrolimus (CNI), or sirolimus (mTOR inhibitor). We did not observe a significant difference in surrogates of systolic or diastolic function in treated cardiac organoids. We pursued single cell-RNA sequencing of drug-treated cardiac organoids and identified gene expression changes consistent with increased extracellular matrix deposition and fibroblast activity in response to CNI treatment. In addition, CNI-treated cardiac organoids cellular composition was notable for increased proportion of fibroblasts and less cardiomyocytes compared to mTOR inhibitor-treated cardiac organoids. To validate gene expression changes observed, we treated cardiac fibroblasts with drugs and observed an increase in collagen production in response to CNI treatment and a reduction in fibroblast number and collagen production in response to mTOR inhibitor treatment. Furthermore, we observed increased ATP production in CNI-treated cardiac fibroblasts, but a reduction in mTOR-treated counterparts. Conclusion: We identify reduced extracellular matrix deposition and cardiac fibroblast proliferation in response to mTOR inhibitor as a potential mechanism for the more favorable remodeling profile observed clinically.
Abstract P3095: Correlating Spatial Wall Shear Stress With Transcriptomics In Pre-calcific Stages Of Bicuspid Aortic Valve Disease
Authors: Hail B Kazik, Harkamaljot S Kandail, Julie Kessler, El-sayed Ibrahim, Ben Goot, John F LaDisa, Joy Lincoln
Journal: Circulation Research (2022)

Bicuspid aortic valve (BAV) is the most common congenital cardiovascular defect and characterized by formation of two, rather than three cusps. Approximately 50% of young adults with BAV prematurely develop calcification and significant stenosis, which is typically more severe in right/non-coronary (R/NC) fusion. Mechanisms underlying this process are unknown. However, based on BAV-induced narrowing of the valve orifice and obstruction of blood flow, it has been speculated that abnormal biomechanical stimuli play a major role. Despite this, validation studies correlating these stimuli to molecular changes that promote calcification in BAV are lacking. Our objective is to define biomechanical stimuli in young patients and mice with R/NC BAV prior to calcification onset, and further use the murine model to correlate biomechanical indices with transcriptomic changes indicative of mechanosensitive regulators of calcification.Fluid-structure interaction (FSI) models and quantified biomechanical indices (wall shear stress (WSS), von Mises stress) are being generated from echocardiography and MRI from young adults and NfatC1 cre(+) ;Exoc5 fl/+ mice with R/NC BAV, and age-matched tricuspid aortic valve controls. In parallel, tissue sections collected from diseased mice are being subject to spatial transcriptomics (10x Visium) to determine the localization of differentially expressed genes relative to abnormal biomechanical stimuli. FSI results from a 23 y/o BAV patient indicate that cusp fusion leads to higher WSS on the fibrosa surface compared to the control, and high von Mises stress at the fusion site, both of which are regions prone to calcification in humans. To date, we have identified aortic valve stenosis in 25% NfatC1 cre(+) ;Exoc5 fl/+ mice, and spatial transcriptomics in these mice is currently underway. To our knowledge these are the first FSI models to characterize biomechanical stimuli for a young adult with R/NC BAV prior to calcification. Our FSI studies in mice will validate the use of a mouse model to study human disease by comparison of biomechanical indices. Furthermore, parallel transcriptomic studies in BAV mice will allow us to correlate biomechanical stimuli with transcriptomic changes underlying premature calcification.
Abstract P3038: Upregulation Of The Mitochondrial Calcium Uniporter Abolishes Mitochondrial Dysfunction Associated With Obesity In Vascular Smooth Muscle Cells
Authors: Jade Avery, Sharon Francis
Journal: Circulation Research (2022)

Obesity is a growing national epidemic that is associated with an increased prevalence of arterial disease. We found that aortic medial hypertrophy during obesity was accompanied by upregulation of serum and glucocorticoid-inducible kinase 1 (SGK1) and reduced mitochondrial oxidative capacity of vascular smooth muscle cells (VSMC). Interestingly, VSMC-specific deletion of SGK1 attenuated obesity-related aortic remodeling and restored mitochondrial oxidative capacity in VSMC implicating a mediator role for SGK1 in mitochondrial dysfunction during obesity. The mechanistic basis for impaired mitochondrial respiration during obesity in VSMC is unknown. Thus, due to its fundamental role in stimulation of mitochondrial oxidative phosphorylation, the current study will investigate the mitochondrial calcium uniporter (MCU) in obesity-related mitochondrial dysfunction in VSMC. As SGK1 is known to regulate the expression and/or activity of ion channels, we hypothesize that upregulation of SGK1 during obesity negatively regulates MCU expression, mitochondrial oxidative activity, and ATP production. MCU protein levels were assessed by western blot analysis. Mitochondrial oxidative activity and ATP production rate were measured using the Agilent Seahorse XF Cell Mito Stress Test and the ATP Rate Assay, respectively in cultured wildtype and SGK1 knockout aortic VSMC from low-fat (LF) control and high-fat (HF) obese mice. To assess the importance of MCU, both assays were performed in the presence or absence of the MCU inhibitor, Ru360. Obesity caused a significant decrease in MCU abundance, but SGK1 deletion resulted in enrichment of MCU in VSMC. Ru360 treatment reversed the increase in basal mitochondrial respiration. We found that obesity reduced overall ATP production by diminishing ATP production from glycolysis and mitochondrial respiration. However, SGK1 deletion enhanced ATP production from glycolysis and mitochondrial respiration during obesity and this effect was attenuated by Ru360. These findings demonstrate that SGK1 negatively regulates MCU expression and activity and imply that augmentation of MCU-driven mitochondrial oxidative activity may underlie the protective effects of SGK1 inhibition on the vascular during obesity.
Massive melanoptysis: a serious unrecognized complication of coal worker's pneumoconiosis
Authors: JA Mosquera
Journal: European Respiratory Journal (1988)

Black sputum is produced when cavitation of progressive massive fibrosis occurs due to mycobacterial and anaerobic bacterial infections (67%) or ischaemic necrosis. The blackish or greyish sputum suggests cavitation of conglomerated masses; the acinar shadows in gravity dependent areas together with cavitary pneumoconiosis, make us suspect an insufficiency of bronchial clearing. Bronchoscopy confirms the diagnosis by showing the airway blocked by dark material. During melanoptysis the patient suffers respiratory failure which can be fatal. Close vigilance of the arterial blood gases is essential. Measures must be taken to maintain clear airways. Melanoptysis should be listed with the other complications of coal worker's pneumoconiosis.
Abstract P2048: Matricellular Protein Cilp1 Promotes Myocardial Fibrosis In Response To Myocardial Infarction
Authors: Qingjun Zhang, Yu He, Yongnan Li, Jun Liao, Qun S Zang, Zhiping Liu
Journal: Circulation Research (2022)

Rationale: Cartilage intermediate layer protein 1 (Cilp1) is a secreted extracellular matrix (ECM) protein normally associated with bone and cartilage development. Its function and mechanism of action in adult heart disease remain elusive. Objective: To establish the function and mechanism of action of Cilp1 in post-myocardial infarction (MI) cardiac remodeling. Methods and Results: We investigated the expression of Cilp1 in mouse models of pathological cardiac remodeling and human heart failure patients. Cilp1 was expressed predominantly in cardiac fibroblasts and upregulated in response to cardiac injury and in the heart and blood of heart failure patients. We generated Cilp1 knock out (KO) and transgenic (Tg) mice with N-terminal half of the protein (NCilp1) overexpressed in myofibroblasts. Cilp1 KO mice had better cardiac function, reduced number of immune cells and myofibroblasts, and enhanced microvascular survival after MI compared to wild-type (WT) littermates. Conversely, NCilp1-Tg mice had augmented loss of cardiac function, increased number of myofibroblasts and infarct size after the MI injury. RNA-seq and gene ontology analysis indicated that cell proliferation and mTORC1 signaling were downregulated in KO hearts compared to WT hearts. In vivo BrdU labeling and immunofluorescence staining showed that myofibroblast proliferation in the Cilp1 KO heart was downregulated. Biaxial mechanical testing and ECM gene expression analysis indicated that while MI caused significant stiffness in WT hearts it had little effect on KO hearts. Upregulation of collagen expression after MI injury was attenuated in KO hearts. Recombinant CILP1 protein or NCilp1-conditioned medium promoted proliferation of neonatal rat ventricular cardiac fibroblasts via the mTORC1 signaling pathway. Conclusions: Our studies established a pathological role of Cilp1 in promoting post-MI remodeling, identified a novel function of Cilp1 in promoting myofibroblast proliferation, and suggested that Cilp1 may serve as a potential biomarker for pathological cardiac remodeling and target for fibrotic heart disease.
Colo-pleural fistula
Authors: LL Olesen, JT Pedersen
Journal: European Respiratory Journal (1989)

A case of non-traumatic colo-pleural fistula is recorded for the first time as the cause of a long-standing pleural empyema. The patient was treated with drainage, antibiotics and parenteral nutrition. The fistula was the result of a diverticulitis coli and/or a pancreatitis.
Abstract P1050: Activation Of Bk <sub>Ca</sub> Channel Increases Myocardial Infarction After Ischemia-Reperfusion Injury In Neonatal Hearts
Authors: Shridhar Sanghvi, Kalina Szteyn, Devasena Ponnalagu, Divya Sridharan, Alexander Lam, Inderjot Hansra, Ankur Chaudhury, Uddalak Majumdar, Andrew Kohut, Shubha Rao, Mahmood Khan, Vidu Garg, Harpreet Singh
Journal: Circulation Research (2022)

Large-conductance calcium and voltage-activated potassium channels (BK Ca ) are heterogeneously expressed in a wide array of cells. In adult ventricular cardiomyocytes, activation of mitochondrial BK Ca channels is implicated in cardioprotection against ischemia-reperfusion (IR) injury. However, plasma membrane BK Ca channel activity has never been detected in adult ventricular cardiomyocytes. In this study, we report the presence of the BK Ca channel in the plasma membrane and mitochondria of neonatal murine and rodent cardiomyocytes. In neonatal cardiomyocyte (NCM), whole-cell potassium currents measured were sensitive to iberiotoxin (IbTx), suggesting the presence of BK Ca channels in the plasma membrane. Moreover, the open probability of single-channel recording decreased in presence of IbTx by 46+5% (n=10) and 32+5% (n=10) for rats and mice, respectively. Ex vivo studies with isolated neonatal hearts (p6) subjected to ischemia and post-conditioned with NS1619 during reoxygenation increased (58+3% as opposed to 48+5% for control, n&gt;5 pups) the myocardial infarction whereas IbTx reduced (32+2%) the infarct size. In agreement, isolated NCM also presented increased apoptosis on treatment with NS1619 during hypoxia-reoxygenation (HR), whereas IbTx reduced TUNEL positive cells. In NCMs, activation of BK Ca channels increased the intracellular reactive oxygen species post HR injury. Electrophysiological characterization of NCMs indicated that NS1619 increased the beat period, field, and action potential duration, and decreased the conduction velocity and spike amplitude. In contrast, IbTx had no impact on the electrophysiological properties of NCMs. Taken together, our data established that inhibition of plasma membrane BK Ca channels in the neonates protects the heart/cardiomyocytes from IR injury. Furthermore, the functional disparity observed towards the cardioprotective activity of BK Ca channels in adults compared to neonatal heart could be attributed to their differential localization.
Abstract P3029: Role Of Histone Deacetylase 9 In The Development Of Adipose Tissue Senescence And Mitochondrial Dysfunction
Authors: Brandee M Goo, Samah Ahmadieh, Abdalrahman Zarzour, Praneet Veerapaneni, David Kim, Stephen Cave, Mourad Ogbi, Jenny Nguyen, Yun Lei, Xin-Yun Lu, Ha Won Kim, Neal L Weintraub
Journal: Circulation Research (2022)

Background: The prevalence of obesity increases with age and is a major risk factor for the development of cardiovascular disease. Our previous studies showed that histone deacetylase 9 (HDAC9) gene deletion protected mice against obesity-associated metabolic disorder. Here, we hypothesized that HDAC9 expression during aging plays an important role in the development of adipose tissue senescence and mitochondrial dysfunction. Methods and Results: Visceral adipose tissue from 20-month-old wild type (WT) mice showed increased expression of HDAC9 (2-fold), p16 (5-fold) and p21 (2-fold) compared to 3-month-old mice. In addition, HDAC9 expression in human subcutaneous adipose tissue positively correlated with age (r 2 =0.088, p=0.034). Furthermore, 1-year-old HDAC9 knockout (KO) mice were protected against the development of age-associated weight gain compared to age-matched WT, in conjunction with reduced levels of senescence-associated beta-galactosidase (SABG) staining and lower expression of p16 (0.7-fold) and p21 (0.5-fold). Interestingly, preadipocytes, which reside in adipose tissue and replenish aged adipocytes, were protected against H2O2 and UV-light induced senescence as evaluated by SABG staining, p16 and p21 expression. Next, we measured adipose tissue mitochondrial function, which is mechanistically linked to senescence, using the Seahorse analyzer. HDAC9 KO significantly increased adipose tissue mitochondrial oxygen consumption rate (e.g., increased basal respiration, proton leak and ATP production). To gain further mechanistic insight, we performed RNA-sequencing of WT and KO adipose tissues and identified thiosulfate sulfurtransferase (TST), an enzyme that is reduced in human obesity and modulates mitochondrial function, as one of the potential mediators for adipose tissue senescence and metabolism. Interestingly, TST expression was reduced in 1-year-old compared to 3-month-old mice (0.2-fold) and enriched in KO compared to WT (4-fold) adipose tissue by qPCR analysis. Conclusion: HDAC9 plays a crucial role in the development of adipose tissue senescence, potentially through regulation of TST and mitochondrial function and may be a promising target to maintain healthy adipose tissue during aging.
Abstract P1096: Kinase-independent Function Of PI3Kgamma Modulates Calcium Re-uptake By Regulating CamKII Mediated Phospholamban Phosphorylation
Authors: Maradumane L Mohan, Conner Witherow, Robert Papay, Yu Sun, Kate Stenson, Sathyamangla V Naga Prasad
Journal: Circulation Research (2022)

Although phosphoinositide 3-kinase (PI3Kγ) null mice (PI3Kγ -/- ) show increased ventricular rate/contraction, it is unknown whether PI3Kγ regulates calcium recycling machinery underlying this phenotype. Primary adult cardiomyocytes from PI3Kγ -/- mice show reduced calcium reuptake by sarcoendoplasmic reticulum (SR) following caffeine. Unexpectedly, PI3Kγ -/- cardiomyocytes showed significant reduction in phosphorylation of phospholamban (PLN) at Thr17, a key regulator of SR calcium re-uptake. Furthermore, loss in PLN phosphorylation in PI3Kγ -/- cardiomyocytes was associated with augmented interaction with SR calcium ATPase (SERCA). Surprisingly, cardiomyocyte-specific overexpression of kinase-dead PI3Kγ (PI3Kγ inact ) in global PI3Kγ -/- mice (PI3Kγ inact /PI3Kγ -/- ) normalized caffeine-induced calcium re-uptake, PLN phosphorylation at Thr17 and decreased PLN-SERCA interaction. These data suggested kinase-independent function of PI3Kγ in regulation of SR calcium load and PLN phosphorylation. Since phosphorylation of Thr17 of PLN is carried out by Ca 2+ /Calmodulin dependent protein kinase (CamKII) we probed for the role of PI3Kγ in regulation of CamKII in PLN phosphorylation. Mechanistically, PI3Kγ exhibits scaffolding function in recruitment of CamKII to PLN at SR to mediate PLN phosphorylation. The study unravels a yet to be recognized kinase-independent role of PI3Kγ in regulating PLN with implications in cardiac function.
Abstract P3032: Liver-directed Mitochondrial Uncoupling Attenuates The Progression Of Early And Late-stage Atherosclerosis In Mice
Authors: Leigh A Goedeke, Xinbo Zhang, Jonathan Sun, Alberto Canfran-Duque, Noemi Rotllan, Ali Nasiri, Mario Kahn, Xian-Man Zhang, Carlos F Fernandez Hernando, Gerald Shulman
Journal: Circulation Research (2022)

Atherosclerotic cardiovascular disease (CVD) remains a leading cause of morbidity and mortality in people with type 2 diabetes (T2D) and new therapies are urgently needed. We recently developed an orally available, liver-directed controlled-release mitochondrial protonophore (CRMP) and showed that this agent safely reverses hypertriglyceridemia, fatty liver, and T2D in rodent and nonhuman primate models of obesity by promoting a subtle sustained increase in hepatic mitochondrial inefficiency. To determine the effect of CRMP on atherogenesis, we performed intervention studies in which 12-week Western-diet fed Ldlr -/- mice with established atherosclerosis were treated with CRMP (30 mg/kg-day) or vehicle control for an additional 12 weeks. CRMP-treated mice displayed a significant reduction in fasting plasma and hepatic triglyceride content, independently of changes in body weight, fasting plasma glucose, insulin or cholesterol levels. Morphometric analysis of the aortic root and brachiocephalic artery revealed that CRMP treatment significantly reduced total plaque area and neutral lipid accumulation. CRMP treatment also decreased markers of plaque vulnerability, as evidenced by a reduction in necrotic core area and increase in fibrous cap area ( P &lt;0.05 vs veh). To determine the mechanisms by which CRMP attenuated atherosclerosis, we performed progression studies in Ldlr -/- mice fed a Western diet containing CRMP or vehicle control for 12 weeks. Similarly to the intervention studies, CRMP significantly reduced aortic root plaque area, neutral lipid accumulation and necrotic core area. These changes were associated with a reduction in plasma triglyceride content and improvement in whole-body insulin sensitivity as assessed by hyperinsulinemic-euglycemic clamps (all P &lt;0.05 vs veh). Single-cell RNA sequencing of whole aortas from CRMP and vehicle-treated Ldlr -/- mice revealed that CRMP reduced the frequency of inflammatory macrophages compared to vehicle (~19% vs ~2%), consistent with an immune-dampening effect of CRMP. Taken together, these data support an anti-atherogenic role for CRMP and suggest the therapeutic potential of liver-directed mitochondrial uncouplers for the treatment of early and late-stage atherosclerosis.